Without peripherals, your communication with your computer would be far more limited. Peripherals are the devices external to your computer that take in information, allow the computer to put out information in visible and audible form, and perform other important tasks. Devices such as printers, scanners, audio and visual equipment and external drives allow us to make full use of the computer's resources. All of these devices hook up electronically via cables or wireless connection to the main computer, but are separate from the main operating functions of the computer.
Printers provide the means for the computer to output information in portable form. Whether a document, a photograph or even an image on canvas (for more sophisticated devices) a printer allows us to reproduce information and share it with others.
Scanners are input devices that give the means to insert information into a computer. They can be used for visual information such as photographs or drawing, or teamed with type-reading software to import documents and translate the hard copy to text that can be edited in word processing programs. Some scanners are sensitive enough to produce a images that are many millions of megabytes in size from an image as small as a slide.
Audio peripherals are both input and output devices. Microphones make it possible to put our voice into the computer and onto the web, or record an instrument. They need a special jack (usually called a "stereo-mini") though better mics can be used with the proper adapters or external hardware. Most high-end recording studios now operate exclusively with computerized inputs and sound boards. Speakers are another peripheral that output music and other audio.
Video cameras work with the microphones to create a complete audio/visual input that can be edited on the computer and viewed, or uploaded to a video website. To view video, the visual output is the monitor, not considered a peripheral as it is vital to computer function. Some computers have a microphone and camera built in, in which case they are not commonly considered peripherals.
External drives or memory can be much larger in size (in terms of gigabytes of storage) than the hard drives on a computer, or small in memory and portable enough to slide into a shirt pocket. They provide storage for digital information that is too voluminous for the hard drive within the computer, and the means to physically transport this information easily.